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Abstracts of Papers

Australian and New Zealand College of Anaesthetists groups before and after the intervention. Annual Scientific Meeting, 7 to 11 May, 2018, Sydney Results: 50 cases were included in the initial audit. Intra- Convention and Exhibition Centre, Sydney, New South operative re-dosing rates were low, with overall compliance Wales of 34% in the January period. The target sample size for the post-intervention period was unable to be reached due to a lack of cases greater than 3 hours' over the audited period. 42 cases were included in the post-intervention analysis. These abstracts are published as supplied and have not been 36% of patients received repeat intra-operative dosing when subjected to editorial review, correction or styling. ANZCA is indicated in the post-intervention group. There was no responsible for obtaining author permissions for publication significant improvement in re-dosing rates post intervention and ethics considerations. [Percentage difference 2%, Chi-squared = 0.04 (95% CI -16.83 to 21.03, p=0.84)]. Conclusion: There was no significant improvement in intra- Improving cephazolin re-dosing practices operative cephazolin re-dosing practices with an educational Dr Luke Anderson (John Hunter Hospital, University of intervention based on audit-feedback cycling and guideline Newcastle, Newcastle, NSW), Dr Robert Marr (Monash dissemination. This is consistent with the low efficacy of Medical Centre, Melbourne, Victoria) educational interventions seen in the literature. Reminder Introduction: Surgical site infection (SSI) is a common, based interventions have been shown to have the greatest preventable cause of post-operative morbidity. Intraoperative effect in improving re-dosing rates. This will form the next re-dosing of cephazolin is recommended for surgical intervention as a part of continued plan-do-study-act (PDSA) procedures extending beyond two half-lives of the drug, to cycling. Due to the absence of electronic intraoperative decrease the risk of SSI. Failure to re-dose is an independent prescribing at our institution, a smartphone app will be risk factor for the development of SSI. Despite re-dosing developed to deliver reminders to clinicians responsible for recommendations, compliance is low, with rates of 20-27% intra-operative re-dosing. reported in the literature. Reminder based interventions have improved re-dosing rates from 20% to 58%. Intraoperative Improving the Fidelity of Cardiopulmonary Exercise Testing decision support systems have led to re-dosing rates of (CPET) for Preoperative Risk Assessment in Major Non- 84-98%. The aim of this project is to improve intraoperative Cardiac Surgery cephazolin re-dosing to comply with guidelines 60-80% of the Dr Jarrod Basto (Peter MacCallum Cancer Centre, University time over a 6 month period. of Melbourne, Melbourne, Victoria), Dr Hilmy Ismail (Peter Method: A retrospective audit of anaesthetic records was MacCallum Cancer Centre, University of Melbourne), Dr conducted to obtain a baseline rate of re-dosing. This was Michael Li (Peter MacCallum Cancer Centre, University of followed by an education-based intervention, consisting of Melbourne), Dr Vladimir Bolshinsky (Peter MacCallum Cancer guideline dissemination and feedback of audit results. Cases Centre, University of Melbourne), Ms Jamie Waterland (Peter performed at John Hunter Hospital from January 1st 2017 to MacCallum Cancer Centre, University of Melbourne), Dr January 31st 2017 were audited to produce baseline data. Alan Herschtal (Peter MacCallum Cancer Centre, University The educational intervention occurred in July 2017, and cases of Melbourne), Dr Kate Burbury (Peter MacCallum Cancer from 1st August 2017 to 31st August 2017 were audited to Centre, University of Melbourne), Professor Alexander Heriot observe the effect of the intervention. Cases were included (Peter MacCallum Cancer Centre, University of Melbourne), if an indication for cephazolin prophylaxis was present, Professor Bernhard Riedel (Peter MacCallum Cancer Centre, the patient was 18 years of age or older, and underwent University of Melbourne) a procedure of greater than 3 hours' duration. Cases were Introduction: The traditional paradigm of preoperative CPET excluded if therapeutic antibiotics were used, cephazolin assessment, established three decades ago, places oxygen was not the recommended agent, the patient had a major consumption (VO2; measured at anaerobic threshold [AT] beta-lactam allergy or cardio-pulmonary bypass was used and peak exercise [pVO2]) at the centre of preoperative (due to prolongation of cephazolin half-life). Sample size risk prediction. VO2, is traditionally dichotomised (AT <10- was calculated to detect a significant change in re-dosing 11 mL.kg.min-1 and pVO2 <16 mL.kg.min-1) for ease of practice for subsequent audit cycles. A sample size of 25 surgical risk prediction [1]. Despite an increasingly elderly was calculated to give a power of 0.8 and a two-sided alpha population with higher comorbid disease burden, surgical of 0.05. This sample size was doubled to 50, to increase and anaesthetic practice continues to evolve and undertake study power. Pearson Chi-square (χ2) test was performed more complex surgery within the framework of sub- to determine any statistically significant difference between specialised care. Within this context, these dichotomised

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VO2 values may lack diagnostic fidelity to risk-evaluate and Time-driven activity based costing to model the utility of guide patient optimisation prior to major surgery. In non- parallel induction room redesign in high turnover surgical surgical populations, cardiorespiratory disease associates lists with impaired CO2 output [2] and incompetent chronotropic Dr Jarrod Basto (Peter MacCallum Cancer Centre, University response associates with increased mortality. As such, of Melbourne, Melbourne, Victoria), Dr Rani Chahal (Peter we evaluated the utility of: (i) CPET-derived CO2 kinetics MacCallum Cancer Centre, University of Melbourne), (PeCO2; PETCO2; Ve/VCO2) and chronotropic response as risk Professor Bernhard Riedel (Peter MacCallum Cancer Centre, predictors for adverse post-operative outcomes; (ii) standard University of Melbourne) blood tests to improve CPET risk modelling. Introduction: Time-Driven Activity Based Costing (TDABC) Methods: We retrospectively analysed 84 patients is an important tool in quantifying complex costs within undergoing CPET prior to major colorectal surgery. healthcare and has been used to project costs of altered staff Parameters measured: Demographic data, Charlson ratios and workflow modifications prior to implementing Comorbidity Index, conventional preop blood tests process improvements [1]. Under a parallel induction design, (haemoglobin, WCC, neutrophils, albumin) and CPET-derived additional personnel are used to optimise theatre efficiency VO2 (AT, pVO2), VCO2 (VE/VCO2, PETCO2, Pe’CO2), and heart by using an induction room to perform anaesthesia related rate response (HRR) parameters. Postoperative outcomes procedures and induction in subsequent patients but prior assessed: (i) Morbidity using Comprehensive Complication to completing the preceding surgical case. In doing so, the Index (CCI, which considers all Clavien-Dindo graded non-operative time between cases is reduced and this may complications) and (ii) 1-year minimum Overall Survival (OS). potentially improve case throughput [2]. As such, parallel Statistical methods used univariable Cox proportional hazards induction exists in contrast to a traditional serial induction and linear regression analysis. design where patients are induced in theatre sequentially Results: Patients (mean±SD) were 62 (±12) years old, by the same anaesthetic team. Within this context, we used 55% male, 27.8 (±5.6) kg.m-2 BMI and Comprehensive TDABC to model personnel costs and time savings for a high Complication Index (30±19). Univariable modelling showed turnover operating list of breast and melanoma procedures no association between traditional VO2 kinetic parameters under a parallel induction design following an observational and OS (AT; HR=0.89 [0.72-1.10]; p=0.25); pVO2; HR=0.91 trial within theatre. [0.80-1.04]; p=0.15). Peak VO2 corrected for body surface Methods: We instituted an observational trial of serial and area (pVO2/BSA >710mL.min-1.m-2) associated with parallel workflow in theatre among 19 surgical lists (10 reduced postoperative morbidity (p=0.019) and improved OS parallel; 9 serial). Non-operative time was defined from (HR=0.13 [0.03-0.56]; p=0.001). VCO2 kinetics at AT (PETCO2; the final closure of skin until the beginning of surgical HR=0.89 [0.82-0.96]; p=0.004 and PeCO2; HR=0.86 [0.78- preparation. Statistical analysis of non-operative time 0.95]; p=0.003) and HR response to peak exercise (HR=0.10 differences was performed by two-tailed t-tests comparing [0.02-0.48]; p=0.02) were robust predictors of OS. Low mean differences of log-transformed data. Using observed preoperative haemoglobin (p=0.001) and elevated neutrophil process times, we constructed a 6-case model of our all- levels (p=0.01) associated with reduced OS and morbidity, day operating list integrating non-operative time under respectively. Using bivariate analysis, predictive accuracy for either a serial or parallel induction design. Using TDABC we postoperative morbidity and for OS improved significantly subsequently assigned personnel costs to these models based (p<0.01) if pVO2/BSA considered chronotropic response to on differences in personnel input, including an additional peak exercise or preoperative neutrophil count and PeCO2 20 minutes per turnover of anaesthetic nursing input. We at AT, neutrophil count for predictive modelling of postop also evaluated the mean revenue generated from analysed morbidity and OS, respectively. cases using the weighted inlier equivalent separation (WIES) Conclusions: Traditional CPET-derived VO2 parameters of single day admissions to determine potential added value may be outdated in our evolving patient population and from scheduling an additional case. subspecialised surgical care. Peak VO2 indexed to BSA may Results: Our observational trial in theatre demonstrated more accurately inform risk. The kinetics of VCO2 and HR an 11-minute reduction in median non-operative time (p combined with routine blood tests may further refine risk <0.0001) under a parallel induction design (24 minutes; IQR predictive models to assist in identifying at-risk patients and 18-35) compared to a serial induction design (35 minutes, those with modifiable cardiorespiratory disease amenable to IQR 29-44). Modelling this improvement using TDABC, preoperative optimisation. our high turnover list of 6 cases projected a reduced total References: 1. Bolshinsky V, et al., Diseases of the Colon & operating list time of 9.8% (55 minutes) under a parallel Rectum, 61: 124-138, 2018. 2. Hansen JE, et al., Chest, 132: induction design, at an increase of 1.8% to theatre- 977-983, 2007 designated personnel costs for the day. This redesign would allow for an additional typical short duration case, e.g. Wide

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Local Excision, to be performed, with a return on investment costoclavicular inflaclavicular block. Allocation concealment averaging $2,818 and a projected time requirement of 58 occurred using sealed opaque envelopes, which were opened minutes (operative and non-operative time included). after enrolment. Exclusion criteria included inability to give Conclusions: A parallel induction design significantly reduced informed consent, allergy to local anesthetics, narcotic non-operative time within our trial in theatre. Projecting abuse, peripheral neuropathy, coagulopathy, BMI ≻35, and this improvement within our high turnover operating list pregnancy or breastfeeding. Both groups received the same demonstrated a 55-minute saving in total operating list time, volume and concentration of 35 mL of 0.5% ropivacaine expected to come at minimal increase in personnel costs as injected under ultrasound guidance with nerve stimulation. assessed by TDABC. An additional case short duration case, Primary outcome was block onset time and block success at e.g. Wide Local Excision, is likely feasible under this model 30 minutes. Other secondary measured outcomes included and represents value for our all-day, high turnover operating performance times, complications during block insertion lists. (paresthesia, vascular puncture, pleural puncture), patient References: 1. French KE, et al., Healthcare, 4: 173-180, satisfaction, and postoperative complications. Patients were 2015. 2. Sandberg WS, et al., Anesthesiology, 103: 406-418, followed up by phone call at postoperative days one and 2005. seven. Results: Primary outcomes - Overall there was no statistically Costoclavicular vs paracoracoid approach to infraclavicular significant difference between sensory block onset time brachial plexus block: a randomized controlled trial between groups. Similarly, block success at 30 minutes was Dr Brigid Brown (Western University, London, Ontario, the same between both groups, with similar conversion to Canada), Dr Pauline Magsaysay (Western University), Dr general anesthetic and local anesthetic supplementation. Janice Yu (Western University), Dr Yves Bureau (Western Secondary outcomes - No significant difference in total University), Dr Shalini Dhir (Western University) procedure time – paracoracoid - 162 seconds, costoclavicular Background: Infraclavicular brachial plexus block is a regional 188 seconds. Complications during the block – no difference anesthesia technique used for upper limb surgeries below between the groups. Postoperative complications were also the humerus. The traditional method of performing an similar between the groups as was patient satisfaction scores infraclavicular block is using the paracoracoid approach(PC), at day 1 and day 7 postoperative. in which the ultrasound transducer is placed near the Conclusion: In conclusion we have found in this non- coracoid process in the sagittal plane and the cords of the inferiority study that the novel costoclavicular approach of brachial plexus are visualized around the axillary artery. infraclavicular brachial plexus block resulted in similar block However, in this view, the cords are separated from one onset times, block success, and complication rates compared another, there is significant variation in the position of the with the traditional paracoracoid approach. individual cords relative to the axillary artery, and all 3 cords are rarely visualized in a single ultrasound window. Recently, a Effect of adding clonidine to ropivacaine in transversus new approach to the infraclavicular block has been described abdominis plane blocks: a randomized pharmacokinetic in the literature, in which the ultrasound transducer is placed study parallel to the clavicle and the block needle is inserted Dr Jennifer Crawford (Royal Prince Alfred Hospital, University inplane from a lateral direction into the costoclavicular (CC) of Sydney, Sydney, NSW), A/Prof John Loadsman (Royal Prince space. Anatomic studies have described how at this position, Alfred Hospital, University of Sydney), Mr Kenny Yang (Royal the cords are clustered together around the lateral edge of Prince Alfred Hospital, University of Sydney), Prof Peter Kam the artery at a more superficial level compared with the PC. (Royal Prince Alfred Hospital, University of Sydney) The cords and needle may therefore be easier to visualize Introduction: Clonidine has been used successfully to with less needle manipulation to perform the block. Potential prolong the duration of action of local anaesthetics in benefits of this approach may include a faster onset of peripheral nerve blocks, but its mechanism of action in block and lower incidence of vascular puncture. When the this setting remains unclear. Some previous studies have patient’s arm is abducted, the plexus is moved further away supported that clonidine acts via a pharmacodynamic from the pleura adding a level of safety. These studies all mechanism (Kroin et al. 2004) but other studies suggest conclude that there is a need for more research into this that clonidine exerts a vasoconstrictor effect (Kopacz & approach evaluating safety and efficacy. We have undertaken Bernards 2001) similar to adrenaline, limiting the washout of a randomized controlled trial evaluating the feasibility of the local anaesthetic from its site of deposition. Therefore, we CC infraclavicular block. measured plasma ropivacaine concentrations after patients Methods: After ethics approval was obtained, 70 adult received transversus abdominis plane (TAP) blocks with and patients undergoing ambulatory upper limb surgery without clonidine. were enrolled and randomized by a computer-program Methods: Eighty women undergoing laparoscopic randomization to undergo either a paracoracoid or gynaecological surgery were randomly assigned to receive

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1 of 4 TAP block solutions: 3 mg/kg of 0.2% ropivacaine the Penthrox inhaler should deliver useful concentrations of (control), ropivacaine with clonidine 2 mcg/kg (clonidine), sevoflurane for this purpose. The study aimed to evaluate the ropivacaine with 1:400,000 adrenaline (adrenaline), or performance of the Penthrox inhaler delivering sevoflurane, ropivacaine and a subcutaneous injection of clonidine 2 as a precursor to clinical trials. mcg/kg (SC clonidine). Total venous plasma ropivacaine Methods: An apparatus to simulate spontaneous ventilation concentrations were measured up to six hours after the block was established. A Penthrox inhaler was filled with using gas chromatograph mass spectrometry. sevoflurane liquid and connected to the apparatus. A gas Results: There were no significant differences in plasma analyser (Datex Corp) sampled concentrations of sevoflurane. ropivacaine concentrations between the control group Two tidal volumes were tested (500ml and 1000ml), and and the clonidine group at any time point in the study, nor other variables explored were occlusion of the dilutor hole were there differences in the mean maximum ropivacaine on the inhaler and hand-warming the inhaler during delivery concentration (Cmax) or time to maximum concentration and the volume of sevoflurane initially instilled into the (Tmax). The SC clonidine group also did not differ from the inhaler. The baseline trial involved a ventilation pattern of controls. Plasma ropivacaine concentrations in the adrenaline 1000ml x 14bpm, dilutor hole covered, unwarmed and 6mls group were significantly lower than the controls from 10 to of sevoflurane. Comparisons were made with all of the non- 90 minutes (p<0.003), and the Cmax was less than that of the test variables held at these settings. Gas concentrations were control group (1.36 mcg/ml vs 1.99 mcg/ml, p<0.001) with a recorded and displayed graphically. The difference between longer Tmax (103.5 min vs 51.0 min, p=0.001). peak and plateau inspired concentrations and the time until Conclusions: Clonidine at a concentration of 1.35 mcg/ depletion to an inspired concentration less than 0.2% were ml added to ropivacaine in TAP blocks did not produce compared descriptively. vasoconstriction as evidenced by a lack of reduction in Results: The pattern of inspired sevoflurane concentration plasma ropivacaine concentrations, lack of reduction was predictable, with an initial high peak, plateau phase and in Cmax, and lack of prolongation of Tmax. Adrenaline, then a linear decline until exhaustion. A a closed dilutor hole however, did cause vasoconstriction, consistent with previous delivered a higher plateau sevoflurane concentration than studies. The 2 mcg/kg dose of clonidine used in this study open (1.6% vs 0.6%) but depleted the inhaler faster (6min was based on other previous studies but because 0.2% vs 13min). Warming the inhaler resulted in higher plateau ropivacaine and high volume TAP blocks were used in this sevoflurane concentrations (2.1% vs 1.6%) but the inhaler study, the final clonidine concentration may have been too was depleted faster (5min vs 6min). A ventilation pattern of low to cause vasoconstriction. Previous studies that have 500ml x 14bpm compared to 1000ml x 14bpm resulted in demonstrated a vasoconstrictor effect of clonidine have used a higher plateau sevoflurane concentration (2.0% vs 1.6%) clonidine concentrations of 10 mcg/ml or greater (Kopacz and slower depletion from the inhaler (12min vs 6min). An & Bernards 2001). Further studies should evaluate whether instillation volume of 12mls compared to 6mls of sevoflurane a vasoconstrictor effect is present when clonidine is used lead to higher peak concentrations (3.1% vs 2.2%), higher at higher concentrations and investigate the role of other plateau concentrations (1.8% vs 1.6%) and a longer time to possible pharmacodynamic mechanisms of action. depletion from the inhaler (10min vs 6min). References: Kopacz, D.J. & Bernards, C.M., 2001. Effect Conclusions: The Penthrox inhaler delivers clinically useful of clonidine on lidocaine clearance in vivo: a microdialysis concentrations of sevoflurane in a bench model in most trials. study in humans. Anesthesiology, 95(6), pp.1371–1376. The delivery profile follows a predictable pattern of high and Kroin, J.S. et al., 2004. Clonidine prolongation of lidocaine rapidly declining concentration, followed by a plateau at a analgesia after sciatic nerve block in rats Is mediated via the clinically useful concentration, followed by a linear decline hyperpolarization-activated cation current, not by alpha- to zero. The duration of useful plateau delivery is variable adrenoreceptors. Anesthesiology, 101(2), pp.488–494. according to the volume of agent instilled in the agent and can be customised to the expected duration of procedure. Sevoflurane in the penthrox inhaler Further clinical trials are required to investigate if this Dr Timothy Makar (Austin Hospital, Melbourne, Victoria), apparatus can produce reliable anaesthesia or sedation in Dr Ned Douglas, Professor Philip Peyton (Austin Hospital, humans, before consideration of clinical use. Melbourne University) References: 1. Dayan AD. Analgesic use of inhaled Introduction: The Penthrox inhaler was designed to deliver methoxyflurane. Hum Exp Toxicol. 2015 Feb 19;35(1):91–100 Methoxyflurane for analgesia and procedural sedation in ambulance and military settings1. Its performance has only Skin-to-epidural space distance in pregnancy: stronger been assessed for Methoxyflurane, which has not been used association with body mass index than abdominal as an anaesthetic for many years in mainstream anaesthesia. subcutaneous fat thickness Sevoflurane has many advantages over methoxyflurane for A/Prof Victoria Eley (The Royal Brisbane and Women’s procedural sedation. First principles calculations suggest Hospital, The University of Queensland, Brisbane,

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Queensland), Dr Adrian Chin (The Royal Brisbane and BMI was 25.0 (21.9-29.2) kg/m2; 107 (21.7%) had a BMI Women’s Hospital, The University of Queensland), Dr ≥ 30 kg/m2 and the BMI range was 17.3-56.7 kg/m2. The Renuka Sekar (The Royal Brisbane and Women’s Hospital, median (IQR) SCFT was 16.2 (13.0-20.9) mm, range 7.0-73.4 The University of Queensland), A/Prof Tim Donovan (The mm. The median (IQR) skin-to-epidural space distance was Royal Brisbane and Women’s Hospital, The University of 5.0 (4.5-6.0) cm, range 3.0-10.0 cm. There was a significant Queensland), Dr Amy Krepska (The Royal Brisbane and correlation between SCFT and skin-to-epidural space Women’s Hospital, The University of Queensland), Dr distance, r=0.526, p<0.001 and also between BMI and skin- Sheridan Bell (The Royal Brisbane and Women’s Hospital, to-epidural space distance, r=0.682, p<0.001. The adjusted The University of Queensland), Dr Mitchell Lawrence (The R2 value (adjusted for age, parity, premature delivery, mode Royal Brisbane and Women’s Hospital, The University of of delivery) for SCFT was 0.280 and for BMI was 0.464. Queensland), Dr Shaun McGrath (The Royal Brisbane and Conclusions: This novel study demonstrated a moderately Women’s Hospital, The University of Queensland), Mr Lachlan strong correlation between both SCFT and BMI, with skin- Webb (Queensland Institute of Medical Research Berghofer), to-epidural space distance. BMI showed the stronger Dr Alex Robinson (The Royal Brisbane and Women’s Hospital, association, explaining 46% of the variability in skin-to- The University of Queensland) epidural space distance. This study will inform further work Introduction: Body mass index (BMI) is used to classify on the relationship between SCFT, BMI and locating the obesity but does not account for the distribution of adipose epidural space. tissue. Measurement of abdominal subcutaneous fat References: 1. Fox CS, Massaro JM, Hoffmann U, et al. thickness (SCFT) by ultrasound scan (USS) is a surrogate Abdominal Visceral and Subcutaneous Adipose Tissue measure for central obesity1 and predicts adverse pregnancy Compartments: Association With Metabolic Risk Factors in outcomes.2 This study determined if the abdominal SCFT the Framingham Heart Study. Circulation 2007;116:39-48. measured at the routine 18-22 week USS was correlated with 2. Kennedy NJ, Peek MJ, Quinton AE, et al. Maternal skin-to-epidural space distance during labour epidural or abdominal subcutaneous fat thickness as a predictor for caesarean section (CS) and compared this with BMI. adverse pregnancy outcome: a longitudinal cohort study. Methods: We analysed a sub-set of participants from a BJOG 2016;123:225-32. single-centre, prospective cohort study that assessed the Pre-operative neurocognitive impairment and delirium in relationship between SCFT and maternity outcomes at a the post-anaesthesia care unit: an observational study tertiary hospital with approximately 4200 annual deliveries Dr Amy Gaskell (Waikato Hospital, University of Auckland, (HREC/14/QRBW/492). An opt-out approach was used. We Auckland, New Zealand), Ms Ashleigh Brough (University of identified those who had received an epidural (for labour Auckland), Ms Abbe Meads (University of Auckland), Prof analgesia) or combined spinal-epidural (for CS) and obtained Jamie Sleigh (Waikato Hospital, University of Auckland) demographic information, mode of delivery and skin-to- Introduction: With the aging population, increasing numbers epidural space distance from the electronic patient record. of patients with neurocognitive impairment will undergo This was a sample of convenience, including only singleton anaesthesia and surgery; these patients are at higher risk pregnancies. Standard cervix-placenta images were obtained of experiencing postoperative delirium. Current guidelines during the routine 18-22 week USS. Three abdominal SCFT for the prevention of postoperative delirium advise routine measurements were subsequently obtained by one trained preoperative cognitive screening to identify patients at high operator and the average calculated. Pearson’s correlation risk[1]. Delirium in the post-anaesthesia care unit (PACU) has coefficient was calculated to describe the relationship been linked to further episodes of postoperative delirium between SCFT and skin-to-epidural space distance. This was and other adverse outcomes[2], however the optimal repeated for the booking BMI and skin-to-epidural space method of measuring early neurocognitive recovery following distance, to determine which relationship was stronger. anaesthesia is not clear. The 3-Minute Diagnostic Assessment Linear regression was used to test for strength of association for Delirium using the Confusion Assessment Method and adjusted R2 values calculated to determine if skin-to- (3D-CAM) is a tool validated for the diagnosis of delirium, epidural space distance was more strongly correlated with however it has not been reported in the PACU setting. Our SCFT or BMI. aims were to determine the baseline cognitive status of our Results: Data was obtained for 493 women delivering surgical population, estimate the incidence of PACU delirium, between February 2015 and June 2016 (46% of the total and to appraise the feasibility of preoperative cognitive sample of 1071). The mean (SD) age was 30.5 (5.5) years; screening and 3D-CAM testing in PACU as research tools. 241 (48.9%) were nulliparous, 348 (70.6%) Caucasian and This is a pilot study in preparation for a planned randomised 458 (92.9%) delivered at a gestation >37 weeks. The mode controlled trial of two intraoperative strategies to improve of delivery was as follows: vaginal delivery 242 (49.1%), early neurocognitive recovery following anaesthesia in older emergency CS 137 (27.8%), elective CS 114 (23.1%). The patients. median (IQR) booking weight was 67.5 (60.0-80.0) kg and

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Methods: We recruited patients aged 60 years and older involvement were designed around routine cases, patient undergoing elective surgery at Waikato Hospital. The study transfers, and management of crises. Clinical environments had ethics and local authority approvals and informed included operating theatres, NICU, Diagnostic Imaging (DI), consent was obtained from participants. The Montreal and the Children’s Cancer Centre (CCC). Cognitive Assessment (MOCA) was performed preoperatively Participants were employees from nursing, medicine and 3D-CAM assessments were performed in the post- and administration, who were soon to work in the new anaesthesia care unit. Logistic regression was performed to facility. Prebriefing sessions included orientation to the test the association between preoperative MOCA scores and environment and simulation equipment. Following each performance in the 3D-CAM in PACU. scenario, formal debriefing took place guided by experienced Results: 112 participants underwent preoperative cognitive facilitators. Discussion involved analysis of and reflection on evaluation. The median (IQR) MOCA score was 24 (22-26); performance. Systematic identification of any systems issues 79 (71%) participants scored below the normal range (MOCA together with suggested solutions was then sought. After score over 26) and 11 (10%) participants had a score of 17 the session, participants were asked to complete an online or lower. The MOCA took a median time (IQR) of 12 (10-15) questionnaire to specify any other potential improvements, minutes to complete. Of the 89 participants who underwent and to explore reflection and feelings of improved workforce 3D-CAM evaluations in PACU, 39 (43%) met 3D-CAM criteria preparedness. The primary outcome measure was the for delirium and 74 (83%) had evidence of inattention. number and type of LSTs identified. The secondary outcome 3D-CAM testing took a median (IQR) of 3 (2-4) minutes. measures were the participants’ assessment of the impact of Preoperative MOCA scores were associated with post- simulation on workforce preparedness and the likelihood of operative delirium (unadjusted OR 0.88[0.79-0.99] per MOCA communication of issues of concern in the future. point, p=0.028). Results: Fourteen simulations were implemented over 4 Conclusion: Mild-moderate neurocognitive impairment days and over 50 LSTs were identified. Those of high priority is common in older patients undergoing surgery and is included the failure of two line isolation systems to come associated with PACU delirium. The 3D-CAM appears to be a back online after a system test shut down, inadequate feasible tool for use in the post-anaesthesia care unit. emergency alarm volumes in each theatre, delays in References: 1. Aldecoa C, Bettelli G, Bilotta F, et al. European accessing certain life-saving medications (eg Intralipid) Society of Anaesthesiology evidence-based and consensus- due to storage site location, and equipment, staffing and based guideline on postoperative delirium. European journal ergonomic issues in NICU, DI and CCC. For each high of anaesthesiology 2017;34(4):192-214. 2. Hernandez priority issue identified, relevant leadership reviewed the BA, Lindroth H, Rowley P, et al. Post-anaesthesia care unit proposed solutions and implemented changes. All high delirium: incidence, risk factors and associated adverse priority LSTs were addressed before opening the facility. outcomes. British journal of anaesthesia 2017;119(2):288-90. 60% of participants responded to the online questionnaire. All respondents either agreed or strongly agreed that Simulation to assess latent safety threats and operational their participation in the simulations improved workforce preparedness within anaesthetic locations in a new preparedness. In addition, more than 80% agreed or strongly children’s hospital agreed that they were more likely to communicate issues of Dr Nathalie Gomes (Monash Health, Monash Simulation, concern in the future as a result of the simulation testing. Melbourne, Victoria), Dr Noel Roberts (Monash Health, Conclusions: In-situ simulation is an effective and practical Monash Simulation) means of identifying LSTs and operational preparedness in Introduction: Prior to the opening of Monash Children’s operating theatres and off-the-floor anaesthetic locations Hospital, the Monash Anaesthesia, Simulation and Paediatric within new facilities. In addition, it may increase the Surgical Departments planned and implemented in-situ likelihood that issues of concern are raised by staff once the simulations to detect and rectify latent safety threats (LSTs) facility is open. and assess operational preparedness of anaesthetic and References: Alfredsdottir H, Bjornsdottir K. Nursing associated departments. LSTs have been defined as system- and patient safety in the operating room. J Adv Nurs. based threats to patient safety that can materialize at any 2008;61(1):29-37. Adler MD et al. Use of simulation to test time and are previously unrecognized1. The simulations also systems and prepare staff for a new hospital transition. J provided an opportunity for staff to become more familiar Patient Saf. 2015;00:00. with the new environment, and to practice procedural guidelines within an interprofessional team. Simulation has A pilot study on the perioperative ROTEM changes across been shown to play a meaningful role in systems testing and obesity categories during lower limb joint replacements staff orientation to new departments2. Dr Usha Gurunathan (The Prince Charles Hospital and Methods: Scenarios appropriate for interprofessional University of Queensland, Brisbane, Queensland), Dr Lisa

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Stanton (The Prince Charles Hospital), Dr Rachael Weir (The been linked to adverse outcomes such as postoperative Prince Charles Hospital), Dr Karen Hay (QIMR), Dr Scott thromboembolic complications in the literature. Mckenzie (The Prince Charles Hospital), Mrs Brownyn Pearse Reference: 1. Campello E, Zabeo E, Radu CM, et al. (The Prince Charles Hospital) Hypercoagulability in overweight and obese subjects who Introduction: Major orthopaedic joint surgery such are asymptomatic for thrombotic events. Thromb Haemost. as total hip and knee replacements may contribute to Jan 8 2015;113(1):85-96. 2. Thorson CM, Van Haren RM, hypercoagulability in all patients. Obese patients undergoing Ryan ML, et al. Persistence of hypercoagulable state after joint replacements are reportedly at higher risk of thrombotic resection of intra-abdominal malignancies. J Am Coll Surg. complications than non-obese because of their increased Apr 2013;216(4):580-589; discussion 589-590. clotting tendencies and aspirin resistance (1). Coagulation changes during major joint replacements have been Transnasal sphenopalatine ganglion block for post dural examined using conventional clotting tests, but most of these puncture headache – results of a local case series studies have been old and cannot be fully accepted with Dr Nathan Hewitt (St George Hospital, Sydney, NSW), Dr surgical practice changes (2). Furthermore, these studies Andrea Jeyendra (St George Hospital), Dr Izreen Mohamed have only looked at selective thrombotic or fibrinolytic Iqbal (St George Hospital), Dr Leonard Kalish (The Sutherland markers and their utility detecting hypercoagulability is Hospital, Sydney, NSW) questionable. Functional viscoelastic point of care test such Introduction: Transnasal sphenopalatine ganglion block as ROTEM (rotational thromboelastometry) provides a timely, (SPGB) has been described as a minimally invasive treatment comprehensive assessment of overall clotting pathway. There option for post dural puncture headache (PDPH)1. It may is limited information about the coagulation changes during be safer and as efficacious as the gold standard epidural joint replacements using the rotational thromboelastometry blood patch (EBP)1,2. We report a case series of 16 patients (ROTEM) assays. This necessitates a preliminary study on receiving SPGB to manage PDPH at two sites within the South the coagulation changes in patients undergoing lower Eastern Sydney Local Health District. limb joint replacements and the influence of obesity on Methods: A transnasal SPGB was performed in 16 those changes. Methods: Eligible patients undergoing THR consecutive patients as first line management of a confirmed and TKR were recruited for this study. Their demographic, symptomatic PDPH between June 2016 and December 2017. medical, treatment history and laboratory test results were The SPGB was performed in patients positioned supine with collected. There were no changes in surgical or anaesthetic a slight head down tilt. Co-phenylcaine forte spray was used management. Data on intraoperative factors including type of to topicalise both nasal passages, before cotton tips coated in surgery, duration of surgery, type of anaesthesia, tranexamic 2% viscous lignocaine were inserted along the nasal floor, to acid, transfusion, intraoperative complications were recorded. the nasopharynx bilaterally. Additional 0.5mL aliquots of 0.5% These patients were followed up until discharge. Venous bupivacaine with adrenaline 1:200,000 were applied to the blood samples were taken ROTEM and Multiplate analysis at cotton tip at 5 minute intervals over 20 minutes (total 4mL). four time points, namely, beginning and end of surgery, day 1 The primary outcomes assessed were pain scores (using the and day 3 following surgery. Three different kinds of ROTEM numerical rating scale (NRS)) and opioid requirements pre- assays: INTEM, EXTEM and FIBTEM were performed. and post intervention. Secondary outcomes assessed were Results: Forty seven patients (M=20, F=27) were recruited time to mobilisation, need for further intervention (EBP or for this pilot study. The mean age was 67 +/- 9 years (range: repeat SPGB) and time to hospital discharge. 45-81). Mean BMI: 34 kg/m2(SD:8), waist circumference: 110 Results: There were 18 SPGBs performed on 16 patients cm (SD: 18); Hip circumference: 115 cm (SD: 16), waist to hip (95% female). PDPH following epidural analgesia in obstetrics ratio: 0.96; Neck circumference: 41 cm (SD: 5). Significant accounted for 9/16 (56%), while the remaining 7/16 cases changes (p<0.01) were observed with time; with EXTEM occurred post diagnostic lumbar puncture (LP). Lower decrease in CFT, increase in alpha angle & MCF, with INTEM: pain scores were reported in 83% of patients immediately Decrease in CFT, A10 & MCF, and with FIBTEM: Increase in post SPGB (NRS 5.9 pre- vs. 2.4 post-SPGB; p=0.005), with A10, MCF & alpha angle. With an increasing BMI, both with complete resolution of pain in 39%. However, there was no EXTEM and INTEM, CFT decreased and MCF &A10 increased. reduction in pain score at 24 hours (NRS 5.9 vs. 4.4; p=0.30). On average MCF increased 0.18 units for each additional unit There was no difference in the opioid requirement in the of BMI. These results were significant at the 5% level. 24 hours pre- or post-SPGB (oral morphine equivalent 11mg Conclusion: There was some evidence that ROTEM vs. 13mg; p=0.26). The average time to mobilisation and parameters varied with BMI across the perioperative period. hospital discharge was 11 and 36 hours, respectively. One Specifically, both with EXTEM and INTEM, compared to obstetric patient received a primary SPGB two days following baseline preoperative values, CFT decreased and MCF &A10 a failed EBP with good effect. Five patients required further increased with increasing BMI. Some of these changes have intervention following SPGB. Two patients received a second

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SPGB, which successfully treated the pain in one. In total, 4/9 were included for this project. Overall, 17% (64/381) of the obstetric patients (44%) required an EBP for failed SPGB. No included charts followed all of the ANZCA recommended patient treated with a SPGB following a LP required further guidelines. Specific inadequately documented areas of the intervention. anaesthetic record and its incidence of completion include: Conclusions: SPGB may provide symptomatic relief in mild to name of procedure (95%), date of procedure (84%), name of moderate PDPH. It may be a useful adjuvant allowing early surgeon (43%), ASA score (80%), allergies (98%), anaesthetic symptom control and the optimisation of oral analgesia, consent (80%), name or signature of anaesthetist (90%), eye or sole therapy in mild cases. All non-obstetric, and 56% protection (72%) and airway device (92%). of obstetric patients were discharged without requiring Conclusions: Overall, the number of charts compliant in all an EBP. The SPGB is minimally invasive, easily repeatable ANZCA recommendations was poor. Particularly important and provides promising results in the observed cohort. A areas that were not completed include: planned or actual dedicated prospective multi centre RCT examining its efficacy procedure, name or signature of anaesthetist, consent, is warranted. airway assessment and airway device. Lack of adequate References: 1.Cohen S, Ramos D, Grubb W, Mellender S, documentation in these areas could lead to patient morbidity Mohiuddin A, Chiricolo A. Sphenopalatine ganglion block: and medico-legal issues; the completion rate should be A safer alternative to epidural blood patch for postdural 100%. This project should raise awareness for all hospital puncture headache. Reg Anesth Pain Med 2014;39:563. staff that anaesthetic documentation is important and can be 2.Patel P, Cohen S, Zhao R, Mellender S, Shah S, Grubb W. improved on. Sphenopalatine ganglion block (SPGB) vs epidural blood References: 1. Australian and New Zealand College of patch (EBP) for accidental post dural puncture headache Anaesthetists. The Anaesthesia Record. Recommendations (PDPH) in obstetric patients – a retrospective observation. on the Recording of an Episode of Anaesthesia Care. The American Academy of Pain Medicine Annual Meeting. PS06. Revised 2006. Accessed from: http://www.anzca. California, 2016. edu.au/documents/ps06-2006-the-anaesthesia-record- recommendations-o.pdf (last accessed 25/07/17) Anaesthesia record keeping in an Australian metropolitan tertiary public teaching hospital Post-operative outcomes among patients undergoing Dr Victor Hui (Austin Health, Melbourne, Victoria), Dr Fiona elective hip and knee joint replacements – impact of Desmond (Austin Health) pre-operative anaemia Introduction: The anaesthetic record is the only anaesthetic Dr Dinushka Kariyawasam (Canberra Hospital, ACT Health, related record that documents the patient’s perioperative Canberra, ACT), Miss Dannielle Duong (Western Sydney journey. The Australian and New Zealand College of University, Sydney, NSW), Dr Sharavni Gupta (Blacktown and Anaesthetists (ANZCA) has published a professional Mount Druitt Hospital, Sydney, NSW), Dr Viraj Kariyawasam document detailing what should be recorded in an episode (Blacktown and Mount Druitt Hospital ) of anaesthetic care1. The aim of this project is to determine Introduction: Pre-operative anaemia is associated documentation compliance to college recommendations in with adverse outcomes among patients undergoing an Australian tertiary hospital. elective surgery. These include increased length of stay, Methods: Austin Health is a metropolitan tertiary public post-operative infections and mortality. Older age and teaching hospital in Melbourne, Australia; it provides 980 co-morbidities have also been implicated with poor outcomes beds across three campuses. Patients having surgery at post-surgery. More than 50% of anaemic patients were found Austin Health over a 7 day period were included in this to be iron deficient. audit. Exclusions include: gastroscopy, colonoscopy, flexible Aim: To assess the rate of pre-operative anaemia and cystoscopies, local anaesthetic only procedures without it’s impact on post-operative outcomes among patients sedation, chronic pain procedures and if the patient’s undergoing elective hip and knee replacement surgeries. medical records were not electronically available. Austin Methodology: Patients who underwent elective hip and Health’s anaesthetic records are paper based and require knee surgery at Blacktown and Mount Druitt hospitals the anaesthetist to manually record all data. The patient’s between 1st July 2015 to 30th June 2016 were included. anaesthetic records were retrospectively analysed. The Anaemia was classified according to WHO criteria. Patient primary outcome was the incidence of inadequately demographics, co-morbidities, anthropometry, pre, intra documented anaesthetic records according to the ANZCA and post-operative parameters were collected. Continuous recommendations. This project received ethical approval variables are presented as medians and ranges. Categorical from the Austin Health Human Research Ethics Committee variables are presented as percentages. Kruskal-Wallis and prior to data collection. chi square non-parametric analyses were performed. Binary Results: During the period of 20th to 26th March 2017 logistic regression analysis was performed to identify factors inclusive, 588 patients underwent a procedure and 381 associated with complications.

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Results: A total of 472 patients underwent elective Hip in the obstetric setting1,2. Formal baseline parameters are and Knee replacement surgeries during the study period. yet to be established in normal pregnancy. This prospective 10 patients were excluded due to lack of preoperative observational study aimed to establish baseline parameters haemoglobin. Prevalence of anaemia was 19.7% (n=91). Mild in an Australian obstetric population undergoing elective anaemia was found in 75 patients, while 16 had moderate Caesarean sections (CS). anaemia. Only 14 patients with anaemia had ferritin level Methods: Ethics approval and written informed consent were performed. Patients with anaemia were older and had a obtained. Women undergoing an elective CS were recruited higher comorbidity index. Mean length of stay among all at a tertiary referral hospital during a 12-month period in patients was 7.1 days (SD 5.5). Patients with anaemia had a 2016. The sample included women with uncomplicated significantly higher length of stay compared to non-anaemic and complicated pregnancies. Patients were considered patients (8.64 vs 6.73, p=0.003). They were likely to be “uncomplicated” if obstetrically and medically low risk, readmitted within 30-days post discharge (12.1% vs 5.4%, whilst patients were considered “complicated” if they had p=0.016). They also required higher blood transfusions pre-existing co-morbidities including obesity, pregnancy- compared to non-anaemic patients (14.35 vs 2.7%, related conditions, or on medications affecting coagulation. p<0.0001). A total of 140 (30.3%) patients had complications Patients were recruited from the maternity preadmission post-surgery. Infective (18.0%), renal impairment (8.2%) and clinic if they were booked for an elective CS at greater cardiovascular (5.6%) complications were the commonest than 30 weeks’ gestation. ROTEM® sampling occurred on reported. Anaemia was associated with higher rate of overall insertion of an intravenous cannula pre-operatively. ROTEM® complications (p<0.0001), renal impairment (p<0.0001) and reference ranges were derived by calculating the 2.5 and infective complications (p=0.005). Anaemia was found to be 97.5 percentiles for INTEM/EXTEM/FIBTEM amplitude at 5 an independent predictor of any complication (Odds ratio minutes (A5), amplitude at 15 minutes (A15), coagulation (OR) 2.20, 95% confidence interval (CI) 1.26-3.86, p=0.006), time (CT), maximum clot firmness (MCF) and clot formation renal impairment (OR 3.65, 95%C 1.77-7.54, p<0.0001) and time (CFT). infective complications (OR 1.88, 95%CI 1.03-3.41, p=0.038) Results: Of the 200 women recruited, 132 (59%) were on multivariate regression analysis. uncomplicated and 68 (34%) were complicated pregnancies, Conclusion: Among patients undergoing elective hip and with a mean age of 32.7 years (SD 5.0), median gestation knee surgery, anaemia was associated with increased length of 39 weeks (IQR 38.3-39.3) and median BMI of 25.6 kg/ of stay, 30 day readmission rates, increased blood transfusion m2 (IQR 22.0-29.7), of which 23 (11.5%) had a postpartum rates and complications. Infective and renal complications haemorrhage (PPH) with a median volume of 450 mL (IQR were significantly higher among patients who were anaemic 300-600) blood loss. Forty-six (23%) women were nulliparous pre-operatively. Assessment of anaemia is poorly performed. and 132 (66%) were presenting for a repeat CS. ROTEM® Correcting anaemia may present an opportunity to improve reference ranges were derived based on results from 132 the surgical outcomes in post elective hip and knee patients in the uncomplicated group. The median and replacements. interquartile range (IQR) for selected ROTEM® parameters are as follows: FIBTEM A5 20 mm (IQR 17-22), FIBTEM A15 Rotational thromboelastometry (ROTEM®) in obstetrics: 23 mm (20-25), FIBTEM CT 53 s (50-57), FIBTEM MCF 24 (20- baseline parameters in uncomplicated and complicated 27), FIBTEM CFT 265 (160-628), EXTEM A5 53 mm (50-57), pregnancies. A prospective observational study on elective EXTEM A15 67 mm (65-70), EXTEM CT 54 seconds (s) (49-57), Caesarean section patients EXTEM MCF 70 mm (68-73), EXTEM CFT 64 s (57-72), INTEM Dr Julie Lee (The Royal Brisbane and Women’s Hospital, The A5 51 mm (48-55), INTEM A15 66 mm (63-68), INTEM CT 165 University of Queensland, Brisbane, Queensland), A/Prof s (145-186), INTEM MCF 69 mm (66-71), and INTEM CFT 63 Victoria Eley (The Royal Brisbane and Women’s Hospital, s (54-72). The University of Queensland), A/Prof Kerstin Wyssusek Conclusion: We have provided reference ranges for ROTEM® (The Royal Brisbane and Women’s Hospital, The University values in women with uncomplicated pregnancies presenting of Queensland), A/Prof Jeremy Cohen (The Royal Brisbane for an elective Caesarean section. As expected, these ranges and Women’s Hospital, The University of Queensland), Dr show an increase in coagulability during normal pregnancy John Rowell (The Royal Brisbane and Women’s Hospital, The compared to the non-pregnant population. University of Queensland), Ms Mandy Way (QIMR Berghofer References: 1. King K, Setty S, Thompson K, McGlennan Medical Research Institute), Professor Andre Van Zundert A and Wright A. Rotational thromboelastometry (ROTEM) (The Royal Brisbane and Women’s Hospital, The University Of - the future of point of care testing in obstetrics? Archives Queensland) of Disease in Childhood - Fetal and Neonatal Edition. 2011; Introduction: Rotational thromboelastometry (ROTEM®) is a 96: 120-1. 2. Wegner J and Popovsky MA. Clinical utility of point-of-care test of coagulation. The use of ROTEM® is well thromboelastography: one size does not fit all. Seminars in established in hepatic and cardiac surgery, but not as yet thrombosis and hemostasis. 2010; 36: 699-706.

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Rotational thromboelastometry (ROTEM®) in obstetrics: were as follows: FIBTEM A5 21 mm (IQR 18-24), FIBTEM A15 baseline parameters in uncomplicated and complicated 25 mm (21-27), FIBTEM CT 50 s (48-54), FIBTEM MCF 26 (22- pregnancies. A prospective observational study on 29), FIBTEM CFT 188 (109-391), EXTEM A5 55 mm (52-58), parturients EXTEM A15 69 mm (66-71), EXTEM CT 52 seconds (s) (48-56), Dr Julie Lee (The Royal Brisbane and Women’s Hospital, The EXTEM MCF 72 mm (69-73), EXTEM CFT 59 s (53-70), INTEM University of Queensland, Brisbane, Queensland), A/Prof A5 53 mm (50-56), INTEM A15 67 mm (64-69), INTEM CT 164 Victoria Eley (The Royal Brisbane and Women’s Hospital, s (144-182), INTEM MCF 70 mm (68-71), and INTEM CFT 59 The University of Queensland), A/Prof Kerstin Wyssusek s (52-67). (The Royal Brisbane and Women’s Hospital, The University Conclusion: We have provided reference ranges for ROTEM® of Queensland), A/Prof Jeremy Cohen (The Royal Brisbane in labouring pregnant women. As expected, these ranges and Women’s Hospital, The University of Queensland), Dr show an increase in coagulability during normal pregnancy John Rowell (The Royal Brisbane and Women’s Hospital, compared to the non-pregnant population. The University of Queensland), A/Prof Rebecca Kimble (The References: 1. King K, Setty S, Thompson K, McGlennan Royal Brisbane and Women’s Hospital, The University of A and Wright A. Rotational thromboelastometry (ROTEM) Queensland), Ms Mandy Way (QIMR Berghofer Medical - the future of point of care testing in obstetrics? Archives Research Institute), Professor Andre Van Zundert (The of Disease in Childhood - Fetal and Neonatal Edition. 2011; Royal Brisbane and Women’s Hospital, The University of 96: 120-1. 2. Wegner J and Popovsky MA. Clinical utility of Queensland) thromboelastography: one size does not fit all. Seminars in Introduction: Rotational thromboelastometry (ROTEM®) is a thrombosis and hemostasis. 2010; 36: 699-7. point-of-care test that provides rapid and specific coagulation assessment. The use of ROTEM® is well established in hepatic Use of recovery phase kinetics following cardiopulmonary and cardiac surgery, but not as yet in the obstetric setting1,2. exercise testing to predict postoperative complications and This prospective observational study aimed to establish 1-year mortality after major intra-abdominal cancer surgery baseline parameters in an Australian parturient population. Dr Michael Li (Peter MacCallum Cancer Centre, Melbourne, Methods: The study population was recruited at a tertiary Victoria), Prof Kwok-Ming Ho (Royal Perth Hospital, University hospital via an opt-out approach approved by the local of Western Australia, Murdoch University, Perth, Western ethics committee. Patients were included in the study upon Australia), Dr Amelie Muellem (University of Cologne, presentation to the labour ward at the point of requiring Germany), Dr Luis Cuadros (Peter MacCallum Cancer Centre), intravenous cannulation or venepuncture. The sample Mr Jarrod Basto (Peter MacCallum Cancer Centre), Dr included women with uncomplicated and complicated Hilmy Ismail (Peter MacCallum Cancer Centre, University of pregnancies. Patients were considered “uncomplicated” Melbourne), Prof Robert Schier (University of Cologne), Prof if obstetrically and medically low risk, whilst patients Bernhard Riedel (Peter MacCallum Cancer Centre, University were considered “complicated” if they had pre-existing of Melbourne) co-morbidities including obesity, pregnancy-related Introduction: Over the past decade, cardiopulmonary conditions, or on medications affecting coagulation. Patients exercise testing (CPET) – especially oxygen consumption aged 18 to 55 years inclusive and at greater than 30 weeks’ at Anaerobic Threshold (AT) and at peak exercise (pVO2) – gestation who presented to the obstetric unit in established have been studied for preoperative risk stratification. Less labour were included. There was no exclusion based on attention has been given to significance of CPET parameters co-morbidities. ROTEM® reference ranges were determined during the recovery phase. Studies have shown that by calculating the 2.5 and 97.5 percentiles for the impaired chronotropic response to exercise is associated uncomplicated group for INTEM/EXTEM/FIBTEM amplitude at with an increased risk of morbidity after abdominal surgery. 5 minutes (A5), amplitude at 15 minutes (A15), coagulation 1. Similarly, impaired speed of heart rate recovery (HRR) time (CT), maximum clot firmness (MCF) and clot formation to baseline following a 6-minute walk test has also been time (CFT). reported to associate with increased risk of complications Results: Of 174 women, 107 (61.5%) were uncomplicated, following lung cancer resection. 2. This study aimed to with a mean age of 29.3 years (SD 5.4), median gestation of assess whether a slower HRR after exercise – a marker 39 weeks (IQR 37.1-40.3) and median BMI of 24.3 kg/m2 (IQR of parasympathetic dysfunction – is (a) associated with 21.7-30.4), of which 102 (58.6%) were delivered vaginally an increased risk of postoperative morbidity and 1-year with the remainder proceeding to a CS. 104 (59.8%) women mortality after major cancer surgery, and (b) better than were nulliparous. Postpartum haemorrhage (PPH) was seen other recovery kinetics in predicting these two clinical in 37 (21.3%) parturients with a median blood loss of 400 outcomes. mL (IQR 250-700). The median and interquartile range (IQR) Methods: The ability of the following recovery kinetic for selected ROTEM® parameters of uncomplicated women parameters, including changes in HRR, oxygen uptake (VO2R), mixed expired CO2 (PeCO2), end-tidal CO2 (PETCO2),

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and minute ventilation to carbon dioxide ratio (Ve/VCO2) who are more than 65 years of age, who have sustained measured from the time when peak exercise capacity was poly-trauma or multiple fractures are at an elevated risk of achieved to the 1st, 2nd, 3rd, 4th and 5th minutes after rib fracture induced morbidity and mortality. Following a cessation of exercise, to predict postoperative morbidity and death after isolated thoracic trauma in an older patient at our 1-year mortality after major cancer surgery was assessed in institution, we have reviewed our management strategies and this retrospective cohort study. PeCO2 was calculated using outcomes. We hope to determine the predictors of adverse the Hansen method by dividing 863 by the Ve/VCO2 slope. pulmonary events on patient presentation to hospital to help Area under the receiver-operating-characteristic (AUROC) further refine our pathways of care. curve was used to evaluate the ability of the recovery Methods: Hospital Research Office approval was obtained kinetics to discriminate between patients with and without prior to study conduct. Patients presenting to our institution postoperative morbidity (Grade III or higher Clavien-Dindo between the 1st January 2015 and the 31st December 2016 complications) and 1-year survival. with clinical or radiological evidence of rib fracture were Results: Of the 80 consecutive patients who had had major identified from a trauma database and electronic review of intra-abdominal cancer surgery between September 2013 radiology reports. The primary outcome was the occurrence and August 2015, 13 (16%) patients died upon follow-up. of pulmonary morbidity, defined as either pneumonia or The HRR and VO2R slopes were both significantly different the need for ventilatory support during the index hospital between survivors and non-survivors, with a modest ability admission. Univariate logistic regression was used to to predict 1-year survival (HRR: AUROC 0.74, 95% confidence identify predictors of pulmonary morbidity on presentation interval [CI] 0.59-0.89, p=0.002; and VO2R: AUROC 0.74, to hospital. From these results a multivariate model was 95%CI 0.61-0.86, p=0.008). The post-exercise recovery developed. The performance of the model was assessed kinetics for CO2 exchange parameters (PETCO2, PeCO2, Ve/ through visual inspection and calculation of the area under VCO2) were not significantly different between survivors a ROC curve. Continuous parameters are presented as mean and non-survivors. None of the recovery kinetic parameters (± standard deviation) or median (interquartile range) as including HRR were predictive of high grade postoperative appropriate and number (percent) for categorical data. morbidities. Statistical tests were two-tailed with p<0.05 for significance. Conclusions: This small pilot study showed that both the rate Results: During the study period 293 patients presented with of recovery of the heart rate (HRR) and oxygen consumption rib fractures. There were 224 males (76.5%) and 69 females (VO2R) after maximal exercise were modest predictors for (23.5%). Thirty-two patients (10.9%) experienced pulmonary medium-term survival after major intra-abdominal cancer morbidity. These patients were older (70 (33) years versus surgery but not major postoperative complications. Whether 50 (28), p<0.001), with a greater Charlson score (3 (4) versus combining these two recovery kinetic parameters with 1 (2), p=0.001) and had experienced a greater number of the standard CPET variables, such as AT and pVO2, would fractures (5 (3) versus 3 (3), p=0.004). The Length of Stay enhance the overall predictive ability of CPET is unknown and was greater in patients with pulmonary morbidity (11.4 warrants further investigation. Whether HRR can outperform (16.3) days versus 4.0 (6.0), p<0.001). There were significant other markers of parasympathetic function such as heart rate differences in the rate of Critical Care Unit admission (31.3% variability is also uncertain but deserves comparative studies. versus 15.4%, p=0.03) and mortality at 60 days (21.9% References: 1. Hightower CE, et al. Br J Anaesth versus 3.1% p<0.001). On multivariate modelling factors 2010;104:465-71. 2. Ha D, et al. J Thorac Cardiovasc Surg predictive of pulmonary morbidity were age (Odds Ratio 2015;149:1168-73. (OR) 1.1, 95th% Confidence Interval 1.03 – 1.17, p=0.003), baseline platelet count (OR 1.01, 1.00 – 1.01, p=0.03), A two-year retrospective review of the predictors of baseline albumin (OR 0.87, 0.79 – 0.95, p=0.003), baseline pulmonary morbidity following rib fracture at a tertiary creatinine (OR 1.02, 1.00 – 1.03, p=0.02), baseline presence metropolitan hospital of respiratory comorbidity (OR 4.6, 1.2 – 17.5, p=0.02) and Dr Nicholas Lightfoot (Middlemore Hospital, Auckland, New the Charlson Comorbidity Index (OR 2.1, 1.1 – 3.8, p=0.02). Zealand), Dr Ashley Scott (Northumbria NHS Foundation Trust, The predictive model generated for pulmonary morbidity had United Kingdom), Dr Anna Rainey (Auckland City Hospital, an area under the ROC curve of 0.743 (95th% Confidence Auckland, New Zealand), Ms Hannah Widjaja (University Interval 0.662 – 0.824). At their point of maximisation, the of Auckland, Auckland, New Zealand), Mr Kevin Henshall sensitivity was 0.906 and the specificity 0.479, this yielded a (Middlemore Hospital), Dr Andrew Cameron (Middlemore positive predictive value of 0.176 and a negative predictive Hospital) value of 0.977. Introduction: Blunt chest trauma leading to rib fracture is Conclusion: In this series we have shown that rib fractures a common trauma induced injury. In addition to significant are associated with serious morbidity and at times mortality. pain, patients are at risk of adverse events such as post- We will use our model to standardise care and optimise traumatic pneumonia, mechanical ventilation or death. Those

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referral for advanced pain management and Critical Care experienced hyponatraemia, the hospital length of stay was review. Moving forward we will further validate our model marginally, but significantly prolonged (4.3 (2.1) versus 4.1 and use this information to generate a score to help predict (1.8) days, p=0.04). There was no difference between the Day patient morbidity One (p=0.82) and Day Two (p=0.12) Quality of Recovery-15 scores between those with hyponatraemia and a normal The predictors hyponatraemia following elective primary sodium level. Differences in the time to assisted weight unilateral knee arthroplasty at a tertiary hospital. A bearing following surgery (p=0.35) and thirty-day readmission retrospective review and predictive model rate (p=0.10) were again insignificant. Predictors of Dr Nicholas Lightfoot (Middlemore Hospital, Auckland, hyponatraemia within the first three post-operative days on New Zealand), Mr Navneet Singh (University of Auckland, multivariate modelling were operative duration (Odds Ratio Auckland, New Zealand), Dr Julian Dimech (Middlemore (OR) 0.98, 95th% Confidence Interval 0.97 – 1.00, p=0.04), Hospital), Dr Nicholas Gormack (Counties Manukau loop diuretic use (OR 6.2, 1.5 – 25.6, p=0.01), thiazide District Health Board, Auckland, New Zealand), Dr Joyce Tai diuretic use (OR 3.3, 1.2 – 9.0, p=0.02) and a preoperative (Middlemore Hospital), Dr Andrew Cameron (Middlemore sodium level of 140-145mmol/L (OR 0.09, 0.02 – 0.48, Hospital) p=0.01). Total oral fluid intake during the first three days was Introduction: Knee arthroplasty is a commonly performed not predictive (p=0.06). procedure. There has been a drive to standardise care Conclusion: Hyponatraemia is a common finding such that patient recovery can be accelerated leading to following TKA. This led to prolongation of length of stay of reductions in hospital length of stay. Others have reported approximately five hours. This may be clinically insignificant as to the impact of delirium, constipation and nausea on by itself but when combined with other factors could length of stay after hip and knee arthroplasty. Little has present an opportunity to attain gains in productivity. We been written about the impact of disorders of electrolyte will continue to modify our predictive model with the aim to balance in patients undergoing total joint arthroplasty. We reduce hyponatraemia in this population. hope to determine the rate of hyponatraemia in patients who have undergone knee arthroplasty at our institution Haemoglobin rise during separation from cardiopulmonary and to elucidate any association between hyponatraemia bypass in adults: a prospective observational study and hospital length of stay, alternations in patient specific Dr Dash Newington (The Prince Charles Hospital, Brisbane, recovery metrics and complication profiles. Queensland), Mrs Nicole Tysoe (The Prince Charles Hospital) Methods: University and Hospital Research Ethics approval Introduction: At our institution we noticed that haemoglobin was obtained prior to study conduct. Patients who (Hb) levels often rise sharply during separation from underwent elective primary total knee arthroplasty (TKA) at cardiopulmonary bypass. We designed a study to determine our institution between the 1st January and 31st December if this Hb rise consistently occurs and the magnitude of 2014 were retrospectively enrolled. Fluid balance and any increase. Such knowledge may reduce unnecessary laboratory data was manually extracted from clinical records intraoperative red cell transfusion in cardiothoracic surgical and merged with a pre-existing Departmental TKA database. patients. The primary outcome was the occurrence of hyponatraemia Methods: The study was designed to detect a 2g/L Hb (defined as a sodium level of less than 135mmol/L) during difference with a significance of p<0.05 and a power of the first three post-operative days. Demographic and 80%. All adult patients undergoing elective or emergency outcome data were reported for the two groups. Univariate cardiopulmonary bypass procedures at our institution then multivariate logistic regression with demographic, between 28/12/2017 and 25/01/2018 were recruited. operative, laboratory and pharmaceutical data were then A baseline blood gas was collected prior to initiation of used to identify significant predictors of post-operative cardiopulmonary bypass. At the end of each bypass run, after hyponatremia. Continuous parameters are presented as rewarming, an arterial blood gas was taken from the bypass mean (± standard deviation, SD) or median (interquartile pump. A simultaneous sample taken from the patient’s range, IQR) as appropriate and number (percent) for arterial line was also processed for comparison. A subsequent categorical data. Statistical tests were two-tailed with p<0.05 intraoperative blood gas was taken after separation from for significance. cardiopulmonary bypass at a time determined by the Results: Two-hundred and thirty-six patients underwent treating anaesthetist. A study form was completed for each primary unilateral TKA during the study period. There were patient recording: age, body mass index, surgical procedure, 97 (41.1%) males and 139 (58.9%) females. One-hundred baseline albumin and creatinine, bypass duration, if diuretics and seven (45.3%) patients experienced hyponatraemia were given, if haemofiltration was used, and details of any within the first three post-operative days. These patients fluid or blood products administered by the anaesthetist were older than those who maintained normal sodium levels or perfusionist between the final bypass blood gas and the (70 (IQR 13) versus 65 (12) years, p<0.001). For those who first gas collected after separation from bypass. Blood gas

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samples were processed on one of two Radiometer ABL800 complexity. Following a baseline prevalence audit, we added Flex machines. The machine used to analyse each sample was a multidisciplinary respiratory care bundle to our ERAS documented. program to specifically target PPC. This pulmonary package, Results: 72 patients were included in the study (sample “iCOUGH”, adapted from that piloted at Central Manchester size calculation of 64 plus a 10% margin of safety). Patient University Hospital (UK) [1], combines Incentive spirometry, age ranged from 16-83 years. Surgical procedures included Cough/deep breathing, Oral care, Understanding education, coronary artery bypass grafting, valve surgery, aortic surgery, Get-out-of-bed and Head-of-bed elevation. We implemented adult congenital procedures, atrial myxoma resection, iCOUGH within a typical quality improvement framework of insertion of heartware, pulmonary thromboendarterectomy, OODA (observe, orientate, decide, act) loops. and heart and lung transplants. The median bypass duration Methods: We evaluated the baseline incidence of PPC over was 76 mins. Hb difference from the final bypass sample a two-month period (observe: April–May 2017). Patients to the first sample after separation from bypass ranged included those undergoing major (≥2hours) elective upper from a 5g/L decrease to a 34g/L increase. 64 patients gastrointestinal, colorectal, and head and neck cancer (89%) demonstrated a Hb rise, with 14 patients (19%) surgery with an intermediate-to-high baseline risk of PPC. demonstrating a rise of 10g/L or greater. The data did not The ARISCAT (Assess Respiratory Risk in Surgical Patients in have a normal distribution (skewness 1.679, kurtosis 5.218). CATalonia) score, a validated predictive index of PPC assessed The median Hb increase was 5.5g/L (IQR 2.0-9.0, Z -.6831 baseline risk [2]. ARISCAT scores of 26-44 and ≥45 defined p <0.001) and the mean increase was 6.33g/L (95% CI 4.87- patients at intermediate and high risk of PPC respectively. 7.80, p<0.01) over a median duration of 27 minutes (SD We adapted (orientate-decide) the iCOUGH intervention to 16.758). This occurred despite 21 patients (29%) having include the Active Cycle of Breathing Technique (aCOUGH), received crystalloid (mean 410ml) during separation from and then implemented (act) across a similar cohort of bypass and only 3 patients (4%) having received either patients that were identified during preoperative anaesthetic packed red cells, haemofiltered pump blood or cell-saver clinic visits. The aCOUGH bundle was re-emphasised blood (mean 300ml). There was no significant correlation during patient educational ‘Surgery School (SS)’ sessions between Hb difference and the time lapse between samples, (led by perioperative staff) and on ward visits. Compliance duration of cardiopulmonary bypass, or baseline albumin to aCOUGH components and incidence of PPC were then or creatinine levels. There was a weak positive correlation monitored prospectively (June–November 2017) in all eligible (r = 0.239, sig. 2-tailed 0.004) between baseline Hb and Hb patients (re-observe). A monthly run-chart was created to difference. Hb levels measured from simultaneous samples display the ongoing compliance with aCOUGH against the taken from the bypass pump and patient’s arterial line, and incidence of PPC. from the two machines used to process the samples did not Results: Bundle compliance (≥3 components) rates increased significantly differ. from 56.4% to 78.9% (p=0.01) over the first six months of Conclusions: The majority of patients showed a statistically implementation. Following step-wise delivery of aCOUGH, and clinically significant increase in Hb during separation from and after six months of implementation (October–November bypass. Further studies are warranted to establish why this 2017; n=71) the overall PPC rates reduced from a baseline increase in Hb occurs and to better characterise and predict rate of 43.6% to 26.8% (17/39 vs. 19/71; p=0.07) but this subgroups of patients who do not respond as expected. did not achieve statistical significance. In the subgroup with highest risk of PPC (ARISCAT score≥45) the rate was reduced The effect of a pulmonary bundle of care on postoperative significantly from 83.3% to 16.7% (5/6 vs. 1/6; p=0.02). This pulmonary complications: A quality improvement project reduction in PPC did not achieve statistical significance in Dr David Shan (Peter MacCallum Cancer Centre, University intermediate risk patients, with a reduction from a baseline of Melbourne, Melbourne, Victoria), Dr Rani Chahal (Peter incidence of 36.4% to 27.7% (12/33 vs. 18/65; p=0.38). MacCallum Cancer Centre, University of Melbourne), Dr Conclusion: The aCOUGH bundle of care resulted in a Hilmy Ismail (Peter MacCallum Cancer Centre, University of significant reduction in PPC rates in high-risk patients. Melbourne), Ms Jamie Waterland (Peter MacCallum Cancer Our preliminary data supports the ongoing aCOUGH Centre, University of Melbourne), Professor Bernhard Riedel program, which in conjunction with our SS holds promise (Peter MacCallum Cancer Centre, University of Melbourne) to significantly reduce PPC in at-risk surgical patients. This Introduction: Enhanced Recovery After Surgery (ERAS), a program also has the potential to improve patient satisfaction multimodal perioperative care pathway, aims to achieve through patient engagement during the peri-operative early functional recovery following major surgery. Despite period. Sustained improvement in PPC rate is expected as the widespread delivery of ERAS, postoperative pulmonary components of aCOUGH become refined (by using OODA complications (PPC) remain a common cause of postoperative loops) and self-sufficient (embedded into the clinical culture) morbidity and mortality. Reported incidence of PPC (2%- through ongoing clinician feedback. 40%) is dependent on patient risk factors and surgical

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References: 1. Moore JA, et al. Anaesthesia 72: 317-27, 2017. use on all days when compared with Controls; this was 2. Canet J, et al. Anesthesiology 113: 1338–50, 2010. significant on days two and three (day one mean difference (95% CI): 41mg (-31.7 – 113.7), p = 0.26; day two: 69.3mg Programmed intermittent bolus administration of local (6.3 – 132.2), p = 0.03; day three: 114mg (40.5 – 188), p = anaesthetic provides superior analgesia compared with 0.003). continuous infusion via extra-pleural catheters following Conclusion: Our study has demonstrated a reduction in thoracic surgery: A retrospective analysis OMEDD use with PIB via extra-pleural catheters for three Dr Luke Willshire (Austin Health, Melbourne, Victoria), Dr days post-thoracic surgery, which was significant on day Matthew Kilpin (Austin Health), Dr Bridget Bishop (Austin three. There was also a concomitant reduction in ketamine Health), Dr Brett Pearce (Austin Health) use and no difference in pain scores or ropivacaine dose. This Introduction: Surgically sited extra-pleural local anaesthetic effect was dose dependant, being more evident in the High- (LA) catheters are an effective method of analgesia Dose PIB group. Overall, PIB, particularly in higher doses, for patients following thoracotomy and video-assisted appears to provide superior analgesia to continuous infusion thoracoscopic surgery (VATS). However, there is no consensus when administered via an extra-pleural catheter in thoracic in the literature as to the most beneficial regimen of surgery. LA delivery. Our objective was to determine whether a programmed intermittent bolus (PIB) technique provides Volatile anaesthesia and perioperative outcomes related superior analgesia via an extra-pleural catheter following to cancer (VAPOR­C): An interim report of a feasibility study thoracic surgery when compared to a continuous LA infusion for an international, multi-centre, prospective RCT regimen. Dr Ken Yee (Peter MacCallum Cancer Centre, Melbourne, Methods: We performed a retrospective, single-centred, Victoria), Dr Julia Dubowitz (Royal Melbourne Hospital, observational study assessing 87 adult patients who received Melbourne, Victoria), Dr David Shan (Peter MacCallum an extra-pleural catheter following VATS or thoracotomy. Cancer Centre), Professor Bernhard Riedel (Peter MacCallum Data were collected from our institution’s scanned medical Cancer Centre), Dr Jonathan Hiller (Peter MacCallum Cancer record. Patients were excluded if they underwent multiple Centre), Dr Hilmy Ismail (Peter MacCallum Cancer Centre), Dr procedures, had an oesophagectomy or were opioid tolerant. Alexander Heriot (Peter MacCallum Cancer Centre), Dr Erica All patients received a surgically sited extra-pleural catheter. Sloan (Peter MacCallum Cancer Centre) Patients were stratified into two groups based on the Background: Currently, it is estimated that more than percentage of their total daily ropivacaine dose they received 80% of cancer patients require anaesthesia for either as boluses: Controls (<10%; n=29) and PIB (≥10%; n=55). definitive cancer resection or diagnostic, supportive and Our primary outcome was Oral Morphine Equivalent Daily palliative procedures. General anaesthesia for surgery can Dose (OMEDD) consumption day one post-thoracic surgery. be delivered as either volatile-based general anaesthesia Secondary outcomes included OMEDD consumption on days or as total intravenous anaesthesia (TIVA) using propofol. two and three post-operation, pain scores via the Numeric Both techniques are used routinely in clinical practice and Rating Scale, daily ketamine use, and daily ropivacaine dose. are interchangeable according to anaesthetist preference. Prospective subgroup analysis was performed comparing Preliminary studies suggest that TIVA with propofol and/ Low-Dose PIB (10-<25%; n=34) and High-Dose PIB (≥25%; or neuraxial anaesthesia associate with favourable cancer n=21) against Controls. outcomes. Additionally, antiadrenergic,­ antiinflammatory­ Results: There was no difference between groups in age, strategies including adjunct therapies like nonselective­ weight, gender, BMI and type of surgery. The PIB group had β­blockers and nonsteroidal­ antiinflammatory­ drugs are also lower mean OMEDD consumption on each day post-thoracic associated with improved cancer outcomes. In contrast, surgery compared to Controls, which was significant on day volatile anaesthetic agents may adversely amplify adaptive three (day one mean difference (95% CI): 44.1mg (-8.5 – and pro­survival transcriptional (HIF1α/β­ and PI3K/Akt/ 96.9), p = 0.10; day two: 47.3mg (-5.2 – 99.7), p = 0.08; day mTOR mediated) pathways to accelerate cancer growth. three: 98.1mg (39.7 – 156), p = 0.001). There was a reduction As such, our current anaesthetic techniques may modulate in the number of patients requiring ketamine infusions in these processes to adversely impact on the global burden of the PIB group compared with Controls on each day. This was disease related to cancer. We conducted a feasibility study statistically significant on days two (p = 0.02) and three (p = toward conducting a phase IV, international, multi-centre, 0.04). There was a small difference in maximum pain scores single blind, randomised control trial (VAPOR-C). favouring the PIB group which was not statistically significant. Methods: Patients scheduled for elective, major resection There was no difference in total ropivacaine dose. Subgroup of cancers are currently being recruited and randomised analysis demonstrated a consistently greater effect for the to either volatile or propofol TIVA general anaesthesia. The High-Dose PIB group compared with the Low-Dose PIB group. feasibility trial will measure the ability to recruit eligible The High-Dose PIB group had a greater reduction in OMEDD patients into the study with the criteria of a recruitment

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rate of at least 75% to be considered feasible. The study protocol will also be assessed as feasible if a successful delivery rate of at least 90% of either anaesthetic technique is achieved. Data collection and analysis will be performed to refine the primary endpoints for the larger VAPOR-C study. These endpoints will relate to: Recurrence-free survival, postoperative morbidity and mortality and quality of life outcomes. Results: Screening commenced on 21/8/2017, and the trial has been active for 93 days or 3 months. Of the 255 patients screened from pre-anaesthetic clinic (PAC) and elective theatre lists using the criteria of patient age, cancer, type and stage of cancer 93 patients (36%) met the selection criteria. Of these 93 patients, 66 patients were approached for recruitment and 51 agreed to participate in the trial. The 27 patients that were eligible but were not approached for the trial were either too ill at the time of screening, the incorrect cancer type or the research team was unavailable. 15 patients refused to participate and two patients were considered not appropriate by the treating anaesthetist. The trial achieved a recruitment rate of 77% of eligible patients with 100% of delivery rate of either anaesthetic technique in all procedures undertaken. Reasons for patients not meeting the selection criteria primarily included: incorrect surgical procedure length/type of surgery, metastatic disease or non- English speaking background. A total of 103 blood biomarker time points have been collected to date and will be batched for analysis (CTCs, cytokines, cDNA, flow cytometry) later to identify the most sensitive time points and clinically relevant biomarkers on which the large VAPOR-C trial will focus. Discussion: The trial is currently on track to achieve the required feasibility criteria at Peter MacCallum with several refinements made to the Vapor-C protocol, so that this trial can be performed at future national and international sites.

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